On 11/5/22, Michael Niedermayer <mich...@niedermayer.cc> wrote: > Fixes: signed integer overflow: 22 * -2107998208 cannot be represented in > type 'int' > Fixes: > 51363/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_BONK_fuzzer-5660734784143360 > > Found-by: continuous fuzzing process > https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg > Signed-off-by: Michael Niedermayer <mich...@niedermayer.cc> > --- > libavcodec/bonk.c | 11 +++++++++-- > 1 file changed, 9 insertions(+), 2 deletions(-) > > diff --git a/libavcodec/bonk.c b/libavcodec/bonk.c > index 1695229dbd..40963aa7c6 100644 > --- a/libavcodec/bonk.c > +++ b/libavcodec/bonk.c > @@ -278,10 +278,13 @@ static int predictor_calc_error(int *k, int *state, > int order, int error) > *state_ptr = &(state[order-2]); > > for (i = order-2; i >= 0; i--, k_ptr--, state_ptr--) { > - int k_value = *k_ptr, state_value = *state_ptr; > + int64_t k_value = *k_ptr, state_value = *state_ptr; > > x -= shift_down(k_value * state_value, LATTICE_SHIFT); > - state_ptr[1] = state_value + shift_down(k_value * x, > LATTICE_SHIFT); > + k_value *= x; > + if ((int32_t)k_value != k_value) > + return AVERROR_INVALIDDATA; > + state_ptr[1] = state_value + shift_down(k_value, LATTICE_SHIFT); > } > > // don't drift too far, to avoid overflows > @@ -366,6 +369,8 @@ static int bonk_decode(AVCodecContext *avctx, AVFrame > *frame, > int64_t t64; > for (int j = 0; j < s->down_sampling - 1; j++) { > sample[0] = predictor_calc_error(s->k, state, s->n_taps, > 0); > + if (sample[0] == AVERROR_INVALIDDATA) > + return sample[0]; > sample++; > } > > @@ -374,6 +379,8 @@ static int bonk_decode(AVCodecContext *avctx, AVFrame > *frame, > return AVERROR_INVALIDDATA; > > sample[0] = predictor_calc_error(s->k, state, s->n_taps, t64); > + if (sample[0] == AVERROR_INVALIDDATA) > + return sample[0]; > sample++; > } > > -- > 2.17.1 >
NAK, slowing things down by using int64_t > _______________________________________________ > ffmpeg-devel mailing list > ffmpeg-devel@ffmpeg.org > https://ffmpeg.org/mailman/listinfo/ffmpeg-devel > > To unsubscribe, visit link above, or email > ffmpeg-devel-requ...@ffmpeg.org with subject "unsubscribe". > _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-devel To unsubscribe, visit link above, or email ffmpeg-devel-requ...@ffmpeg.org with subject "unsubscribe".
